package com.cssl.util;

import java.io.*;
import java.net.URL;
import java.net.URLConnection;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
import java.text.SimpleDateFormat;
import java.util.*;

public class HttpRequest {
        /**
 * 向指定URL发送GET方法的请求
 *
 * @param url
 *            发送请求的URL
 * @param param
 *            请求参数，请求参数应该是 name1=value1&name2=value2 的形式。
 * @return URL 所代表远程资源的响应结果
 */
public static String sendGet(String url, String param) {
    String result = "";
    BufferedReader in = null;
    try {
        String urlNameString = url + "?" + param;
        URL realUrl = new URL(urlNameString);
        // 打开和URL之间的连接
        URLConnection connection = realUrl.openConnection();
        // 设置通用的请求属性
        connection.setRequestProperty("accept", "*/*");
        connection.setRequestProperty("connection", "Keep-Alive");
        connection.setRequestProperty("user-agent",
                "Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1;SV1)");

        // 建立实际的连接
        connection.connect();
        // 获取所有响应头字段
        Map<String, List<String>> map = connection.getHeaderFields();
        // 遍历所有的响应头字段
        for (String key : map.keySet()) {
            System.out.println(key + "--->" + map.get(key));
        }
        // 定义 BufferedReader输入流来读取URL的响应
        in = new BufferedReader(new InputStreamReader(
                connection.getInputStream()));
        String line;
        while ((line = in.readLine()) != null) {
            result += line;
        }
    } catch (Exception e) {
        System.out.println("发送GET请求出现异常！" + e);
        e.printStackTrace();
    }
    // 使用finally块来关闭输入流
    finally {
        try {
            if (in != null) {
                in.close();
            }
        } catch (Exception e2) {
            e2.printStackTrace();
        }
    }
    return result;
}
        /**
         * 向指定 URL 发送POST方法的请求
         *
         * @param url
         *            发送请求的 URL
         * @param param
         *            请求参数，请求参数应该是 name1=value1&name2=value2 的形式。
         * @return 所代表远程资源的响应结果
         */
        public static String sendPost(String url, String param, String keyValue) {
            PrintWriter out = null;
            BufferedReader in = null;
            String result = "";
            try {
                URL realUrl = new URL(url);
                // 打开和URL之间的连接
                URLConnection conn = realUrl.openConnection();
                // 设置通用的请求属性
                conn.setRequestProperty("accept", "*/*");
                conn.setRequestProperty("connection", "Keep-Alive");
                conn.setRequestProperty("api-key", keyValue);
                conn.setRequestProperty("user-agent",
                        "Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1;SV1)");
                conn.setRequestProperty("Accept-Charset", "UTF-8");
                // 发送POST请求必须设置如下两行
                conn.setDoOutput(true);
                conn.setDoInput(true);
                // 获取URLConnection对象对应的输出流
                //out = new PrintWriter(conn.getOutputStream());
                out = new PrintWriter(new OutputStreamWriter(conn.getOutputStream(), "UTF-8"));
                // 发送请求参数
                out.print(param);
                // flush输出流的缓冲
                out.flush();
                // 定义BufferedReader输入流来读取URL的响应
                in = new BufferedReader(
                        new InputStreamReader(conn.getInputStream(),"UTF-8"));
                String line;
                while ((line = in.readLine()) != null) {
                    System.out.println(line);
                    result += line;
                }
            } catch (Exception e) {
                System.out.println("发送 POST 请求出现异常！"+e);
                e.printStackTrace();
            }
            //使用finally块来关闭输出流、输入流
            finally{
                try{
                    if(out!=null){
                        out.close();
                    }
                    if(in!=null){
                        in.close();
                    }
                }
                catch(IOException ex){
                    ex.printStackTrace();
                }
            }
            return result;
        }

        public static String generateOrderId(){
            String keyup_prefix=new SimpleDateFormat("yyyyMMddHHmmss").format(new Date());
            String keyup_append= String.valueOf(new Random().nextInt(899999)+100000);
            String pay_orderid=keyup_prefix+keyup_append;//订单号
            return pay_orderid;
        }
        public static String generateTime(){
            return new SimpleDateFormat("yyyy-MM-dd HH:mm:ss").format(new Date());
        }

        public static String md5(String str) throws NoSuchElementException {
            try {
                MessageDigest md = MessageDigest.getInstance("MD5");
                md.update(str.getBytes("UTF-8"));
                byte[] byteDigest = md.digest();
                int i;
                //字符数组转换成字符串
                StringBuffer buf = new StringBuffer("");
                for (int offset = 0; offset < byteDigest.length; offset++) {
                    i = byteDigest[offset];
                    if (i < 0)
                        i += 256;
                    if (i < 16)
                        buf.append("0");
                    buf.append(Integer.toHexString(i));
                }
                // 32位加密
                return buf.toString();//toUpperCase
                // 16位的加密
                //return buf.toString().substring(8, 24).toUpperCase();
            } catch (NoSuchAlgorithmException | UnsupportedEncodingException e) {
                e.printStackTrace();
                return null;
            }
        }
}
